Many adhesives and bonding compounds in present use are derived from petrochemical or organic sources. These materials can emit toxic products or ignite in a fire, often resulting in ignition or degradation of particles bonded therewith to form further toxic products, exposure to which can be fatal in confined spaces.
Other bonding compounds adapted for compositions which will withstand extreme temperatures are kiln dried, fired or otherwise subjected to external heating to achieve satisfactory bonding, e.g., fired bricks, tiles, etc.
Vassilevsky et al, in U.S. Pat. No. 3,483,006, describe a cold-curable cementitious composition composed of MgO or semi-calcined dolomite, magnesium sulfate, an alkaline earth metal chloride (XCl.sub.2), an alkali metal silicate (Y.sub.2 SiO.sub.3) and an alkali metal fluorosilicate (Y.sub.2 SiF.sub.6). The cement comprises two complex substances: a Mg(Ca)-oxychloro-sulfate and the combination of XCl.sub.2 -Y.sub.2 SiO.sub.3 -Y.sub.2 SiF.sub.6.
Gajardo et al (U.S. Pat. No. 3,203,813) disclose an insulating material containing an aluminosilicate clay, a water-soluble alkali metal silicate, a foaming agent and an expanded siliceous inorganic aggregate, heated at 300.degree.-400.degree. F. to set the silicate.
Lyass et al (U.S. Pat. No. 3,508,936) obtain a self-hardening mixture for foundry molds containing filler, sodium silicate as binder, dicalcium silicate as hardener, a foaming agent and an abietic resin to increase the strength of the mold.
Other references on siliceous cement or concrete products include:
U.S. Pat. Nos. 3,138,471, Wygant; 3,450,548, Petkus; 3,837,872, Conner; 3,874,887, Dalmatov et al; and 4,030,939, Mallow.